1. Field of the Invention
The present invention relates to a light-emitting diode module for illuminating an instrument panel such as an instrument panel of an automotive vehicle.
2. Description of Related Art
An example of a light-emitting diode module for use in an instrument panel of an automotive vehicle is disclosed in JP-A-2006-128415. In the instrument panel, a scale plate is disposed at a front surface of the instrument panel, and a light-conducting plate is overlapped on a rear surface of the scale plate. Light emitted from the light-emitting diode module is introduced into the light-conducting plate from its side portion, and the light is scattered in the light-conducting plate and reflected frontward toward the scale plate. Thus, the scale plate is illuminated.
In the conventional module, since a member supporting the light-emitting diode sticks out toward the scale plate, the scale plate and the light-conducting plate have to be arranged in a particular manner to effectively introduce the light emitted from the light-emitting diode module into the light-conducting plate. For example, a certain space is provided between the scale plate and the light-conducting plate to make a space for accommodating the sticking-out portion of the supporting member. Alternatively, a portion of the scale plate corresponding to the supporting member is projected toward the front side while keeping a close contact between the scale plate and the light-conductive plate.
However, the light introduced into the light-conducting plate is not fully utilized if the scale plate is separated from the light-conducting plate. To compensate the non-efficient utilization of the light, a luminance of the light-emitting diode has to be increased by supplying a higher power to the light-emitting diode, or the number of the light-emitting diodes used has to be increased. On the other hand, if a part of the scale plate is projected frontward, an ornamental design of the instrument will be damaged.